Stephen F. Cohen is a professor emeritus at New York University and Princeton University. His Soviet Fates and Lost Alternatives: From Stalinism to the New Cold War and his The Victims Return: Survivors of the Gulag After Stalin are now in paperback.

One of the last and irrepressible truth-tellers about the Stalin era, who themselves experienced the horror of those years, has died. Having lost both his mother and father in the 1930s, in the tyrant’s prisons of torture and execution, Anton Antonov-Ovseyenko was arrested three times (in 1940, 1941 and 1948) and spent nearly thirteen years in Gulag forced-labor camps, including the infamous complexes at Pechora and Vorkuta.

Anton had one mission, as he passionately declared in my presence many times during our thirty-seven-year friendship: “To unmask Stalin, his henchmen and their heirs.” The first major result was Anton’s book Portret tirana (Portrait of A Tyrant), written in the 1960s and 1970s, long before it could be published in Russia, but published in English in New York in 1981 as The Time of Stalin. It remains one of the monumental works of historical truth-telling of the pre-Gorbachev and pre-glasnost era, along with Roy Medvedev’s Let History Judge and Aleksandr Solzhenitsyn’s The Gulag Archipelago.

Though legally blind—Anton needed special devices in order to read and write—and working surreptitiously and almost alone, the amount of forbidden information he uncovered, largely in oral and typescript memoirs of other surviving victims, and the volume of his writings were astonishing, even heroic. Researching before Gorbachev ended historical censorship in the late 1980s and before the post-Soviet “archive revolution,” Anton made some factual errors, which today’s historians must certainly understand and forgive....